1 /*
2 * SVG data parser
3 *
4 * Authors:
5 * Lauris Kaplinski <lauris@kaplinski.com>
6 * Raph Levien <raph@acm.org>
7 *
8 * Copyright (C) 1999-2002 Lauris Kaplinski
9 * Copyright (C) 1999 Raph Levien
10 *
11 * Released under GNU GPL, read the file 'COPYING' for more information
12 */
14 #ifdef HAVE_CONFIG_H
15 # include "config.h"
16 #endif
18 #include <cstring>
19 #include <string>
20 #include <cstdlib>
21 #include <cstdio>
22 #include <glib/gstrfuncs.h>
23 #include <libnr/nr-matrix-fns.h>
24 #include <libnr/nr-matrix-ops.h>
25 #include <2geom/transforms.h>
26 #include <2geom/angle.h>
27 #include <libnr/nr-convert2geom.h>
28 #include "svg.h"
29 #include "preferences.h"
31 #ifndef M_PI
32 # define M_PI 3.14159265358979323846
33 #endif
35 bool
36 sp_svg_transform_read(gchar const *str, Geom::Matrix *transform)
37 {
38 int idx;
39 char keyword[32];
40 double args[6];
41 int n_args;
42 size_t key_len;
44 if (str == NULL) return false;
46 Geom::Matrix a(Geom::identity());
48 idx = 0;
49 while (str[idx]) {
50 /* skip initial whitespace */
51 while (g_ascii_isspace (str[idx])) idx++;
53 /* parse keyword */
54 for (key_len = 0; key_len < sizeof (keyword); key_len++) {
55 char c;
57 c = str[idx];
58 if (g_ascii_isalpha (c) || c == '-') {
59 keyword[key_len] = str[idx++];
60 } else {
61 break;
62 }
63 }
64 if (key_len >= sizeof (keyword)) return false;
65 keyword[key_len] = '\0';
67 /* skip whitespace */
68 while (g_ascii_isspace (str[idx])) idx++;
70 if (str[idx] != '(') return false;
71 idx++;
73 for (n_args = 0; ; n_args++) {
74 char c;
75 char *end_ptr;
77 /* skip whitespace */
78 while (g_ascii_isspace (str[idx])) idx++;
79 c = str[idx];
80 if (g_ascii_isdigit (c) || c == '+' || c == '-' || c == '.') {
81 if (n_args == sizeof (args) / sizeof (args[0])) return false; /* Too many args */
82 args[n_args] = g_ascii_strtod (str + idx, &end_ptr);
84 //printf("took %d chars from '%s' to make %f\n",
85 // end_ptr-(str+idx),
86 // str+idx,
87 // args[n_args]);
89 idx = end_ptr - (char *) str;
91 while (g_ascii_isspace (str[idx])) idx++;
93 /* skip optional comma */
94 if (str[idx] == ',') idx++;
95 } else if (c == ')') {
96 break;
97 } else {
98 return false;
99 }
100 }
101 idx++;
103 /* ok, have parsed keyword and args, now modify the transform */
104 if (!strcmp (keyword, "matrix")) {
105 if (n_args != 6) return false;
106 a = (*((Geom::Matrix *) &(args)[0])) * a;
107 } else if (!strcmp (keyword, "translate")) {
108 if (n_args == 1) {
109 args[1] = 0;
110 } else if (n_args != 2) {
111 return false;
112 }
113 a = Geom::Translate(args[0], args[1]) * a;
114 } else if (!strcmp (keyword, "scale")) {
115 if (n_args == 1) {
116 args[1] = args[0];
117 } else if (n_args != 2) {
118 return false;
119 }
120 a = Geom::Scale(args[0], args[1]) * a;
121 } else if (!strcmp (keyword, "rotate")) {
122 if (n_args != 1 && n_args != 3) {
123 return false;
124 }
125 Geom::Rotate const rot(Geom::deg_to_rad(args[0]));
126 if (n_args == 3) {
127 a = ( Geom::Translate(-args[1], -args[2])
128 * rot
129 * Geom::Translate(args[1], args[2])
130 * Geom::Matrix(a) );
131 } else {
132 a = rot * a;
133 }
134 } else if (!strcmp (keyword, "skewX")) {
135 if (n_args != 1) return false;
136 a = ( Geom::Matrix(1, 0,
137 tan(args[0] * M_PI / 180.0), 1,
138 0, 0)
139 * a );
140 } else if (!strcmp (keyword, "skewY")) {
141 if (n_args != 1) return false;
142 a = ( Geom::Matrix(1, tan(args[0] * M_PI / 180.0),
143 0, 1,
144 0, 0)
145 * a );
146 } else {
147 return false; /* unknown keyword */
148 }
149 /* Skip trailing whitespace */
150 while (g_ascii_isspace (str[idx])) idx++;
151 }
153 *transform = a;
154 return true;
155 }
157 #define EQ(a,b) (fabs ((a) - (b)) < 1e-9)
159 gchar *
160 sp_svg_transform_write(Geom::Matrix const &transform)
161 {
162 Inkscape::Preferences *prefs = Inkscape::Preferences::get();
164 double e = 0.000001 * transform.descrim();
165 int prec = prefs->getInt("/options/svgoutput/numericprecision", 8);
166 int min_exp = prefs->getInt("/options/svgoutput/minimumexponent", -8);
168 /* fixme: We could use t1 * t1 + t2 * t2 here instead */
169 if ( Geom::are_near(transform[1], 0.0, e) && Geom::are_near (transform[2], 0.0, e)) {
170 if (Geom::are_near (transform[4], 0.0, e) && Geom::are_near (transform[5], 0.0, e)) {
171 if (Geom::are_near (transform[0], 1.0, e) && Geom::are_near (transform[3], 1.0, e)) {
172 /* We are more or less identity */
173 return NULL;
174 } else {
175 /* We are more or less scale */
176 gchar c[256];
177 unsigned p = 0;
178 strcpy (c + p, "scale(");
179 p += 6;
180 p += sp_svg_number_write_de (c + p, transform[0], prec, min_exp);
181 c[p++] = ',';
182 p += sp_svg_number_write_de (c + p, transform[3], prec, min_exp);
183 c[p++] = ')';
184 c[p] = '\000';
185 g_assert( p <= sizeof(c) );
186 return g_strdup(c);
187 }
188 } else {
189 if (Geom::are_near (transform[0], 1.0, e) && Geom::are_near (transform[3], 1.0, e)) {
190 /* We are more or less translate */
191 gchar c[256];
192 unsigned p = 0;
193 strcpy (c + p, "translate(");
194 p += 10;
195 p += sp_svg_number_write_de (c + p, transform[4], prec, min_exp);
196 c[p++] = ',';
197 p += sp_svg_number_write_de (c + p, transform[5], prec, min_exp);
198 c[p++] = ')';
199 c[p] = '\000';
200 g_assert( p <= sizeof(c) );
201 return g_strdup(c);
202 } else {
203 gchar c[256];
204 unsigned p = 0;
205 strcpy (c + p, "matrix(");
206 p += 7;
207 p += sp_svg_number_write_de (c + p, transform[0], prec, min_exp);
208 c[p++] = ',';
209 p += sp_svg_number_write_de (c + p, transform[1], prec, min_exp);
210 c[p++] = ',';
211 p += sp_svg_number_write_de (c + p, transform[2], prec, min_exp);
212 c[p++] = ',';
213 p += sp_svg_number_write_de (c + p, transform[3], prec, min_exp);
214 c[p++] = ',';
215 p += sp_svg_number_write_de (c + p, transform[4], prec, min_exp);
216 c[p++] = ',';
217 p += sp_svg_number_write_de (c + p, transform[5], prec, min_exp);
218 c[p++] = ')';
219 c[p] = '\000';
220 g_assert( p <= sizeof(c) );
221 return g_strdup(c);
222 }
223 }
224 } else {
225 gchar c[256];
226 unsigned p = 0;
227 strcpy (c + p, "matrix(");
228 p += 7;
229 p += sp_svg_number_write_de (c + p, transform[0], prec, min_exp);
230 c[p++] = ',';
231 p += sp_svg_number_write_de (c + p, transform[1], prec, min_exp);
232 c[p++] = ',';
233 p += sp_svg_number_write_de (c + p, transform[2], prec, min_exp);
234 c[p++] = ',';
235 p += sp_svg_number_write_de (c + p, transform[3], prec, min_exp);
236 c[p++] = ',';
237 p += sp_svg_number_write_de (c + p, transform[4], prec, min_exp);
238 c[p++] = ',';
239 p += sp_svg_number_write_de (c + p, transform[5], prec, min_exp);
240 c[p++] = ')';
241 c[p] = '\000';
242 g_assert( p <= sizeof(c) );
243 return g_strdup(c);
244 }
245 }
248 gchar *
249 sp_svg_transform_write(Geom::Matrix const *transform)
250 {
251 return sp_svg_transform_write(*transform);
252 }
254 /*
255 Local Variables:
256 mode:c++
257 c-file-style:"stroustrup"
258 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
259 indent-tabs-mode:nil
260 fill-column:99
261 End:
262 */
263 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :